Yeast glucan Innate immune response Intestinal microbiota

This study investigates the effects of different levels of commercial yeast glucan (CYG) on innate immune response, hematological parameters, in-testinal microbiota, growth performance and survival rate of white fish (kutum) fry. Specimens (1.1 ± 0.15 g) were randomly allocated into 15 tanks (100 L) at a density of 25 fish per tank and triplicate groups were fed either a basal control diet (0 % CYG) or a basal diet supplemented with yeast (0.5, 1, 1.5 or 2 % CYG) for 60 days. All dietary CYG levels significantly increased the innate immune responses (IgM levels and lysozyme activity) (P < 0.05) and the highest survival was observed in the 1 and 1.5 % CYG group. Compared to the control group, CYG had no effects on RBC, Hct and Hb (P> 0.05), but WBC levels were significantly higher in CYG fed fish (P < 0.05). Microbiological assessment indicated that the viable culturable autochthonous and lactic acid bacteria (LAB) levels significantly elevated in 0.5 and 1 % treatments. Our results indicated that low levels of dietar